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authorHaren Myneni <haren@linux.vnet.ibm.com>2015-10-08 13:45:51 -0700
committerHerbert Xu <herbert@gondor.apana.org.au>2015-10-14 22:23:17 +0800
commitea0b3984c1cc8b28de27a3bec285102b4e366a4c (patch)
treeb0134466a5b790d4091dc16065257a00ea24bf00 /lib/842/842_decompress.c
parentf5128432b08c3e263e1a7ce709d686b1ded51131 (diff)
downloadlinux-ea0b3984c1cc8b28de27a3bec285102b4e366a4c.tar.gz
linux-ea0b3984c1cc8b28de27a3bec285102b4e366a4c.tar.xz
crypto: 842 - Add CRC and validation support
This patch adds CRC generation and validation support for nx-842. Add CRC flag so that nx842 coprocessor includes CRC during compression and validates during decompression. Also changes in 842 SW compression to append CRC value at the end of template and checks during decompression. Signed-off-by: Haren Myneni <haren@us.ibm.com> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'lib/842/842_decompress.c')
-rw-r--r--lib/842/842_decompress.c17
1 files changed, 17 insertions, 0 deletions
diff --git a/lib/842/842_decompress.c b/lib/842/842_decompress.c
index 5446ff0c9ba0..8881dad2a6a0 100644
--- a/lib/842/842_decompress.c
+++ b/lib/842/842_decompress.c
@@ -285,6 +285,7 @@ int sw842_decompress(const u8 *in, unsigned int ilen,
struct sw842_param p;
int ret;
u64 op, rep, tmp, bytes, total;
+ u64 crc;
p.in = (u8 *)in;
p.bit = 0;
@@ -375,6 +376,22 @@ int sw842_decompress(const u8 *in, unsigned int ilen,
}
} while (op != OP_END);
+ /*
+ * crc(0:31) is saved in compressed data starting with the
+ * next bit after End of stream template.
+ */
+ ret = next_bits(&p, &crc, CRC_BITS);
+ if (ret)
+ return ret;
+
+ /*
+ * Validate CRC saved in compressed data.
+ */
+ if (crc != (u64)crc32_be(0, out, total - p.olen)) {
+ pr_debug("CRC mismatch for decompression\n");
+ return -EINVAL;
+ }
+
if (unlikely((total - p.olen) > UINT_MAX))
return -ENOSPC;